The worst potential scenario for sea level rise around the US coastline this century is more than two meters, says an authoritative report issued today by NOAA's Climate Program Office.

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Regardless of how much warming occurs over the next 100 years, sea level rise is not expected to stop in 2100.

More than 8 million people in the US live in areas at risk of coastal flooding. Along the Atlantic Coast alone, almost 60 percent of the land that is within a meter of sea level is planned for further development, with inadequate information on the potential rates and amount of sea level rise.

The report Global Sea Level Rise Scenarios for the United States National Climate Assessment says global sea level rise has been a persistent trend for decades.

It concludes that it is expected to continue beyond the end of this century, which will cause significant impacts in the United States. Scientists have very high confidence (greater than 90% chance) that global mean sea level will rise at least 8 inches (0.2 meter) and no more than 6.6 feet (2.0 meters) by 2100.

Many of the nation's assets related to military readiness, energy, commerce, and ecosystems that support resource-dependent economies are already located at or near the ocean, thus exposing them to risks associated with sea level rise.

The report is published by NOAA's Climate Program Office in collaboration with twelve contributing authors from ten different federal and academic science institutions.

It was produced in response to a request from the U.S. National Climate Assessment Development and Advisory Committee and provides a synthesis of the scientific literature on global sea level rise, and a set of four scenarios of future global sea level rise. The report includes input from national experts in climate science, physical coastal processes, and coastal management.

The authors say they have tried to interpret the qualitative and quantitative information about different aspects of future environmental change to investigate the potential consequences for society.

Scenarios do not predict future changes, but describe future potential conditions in a manner that supports decision-making under conditions of uncertainty.

The report says: "We have very high confidence (greater than 9 in 10 chances) that global mean sea level (based on mean sea level in 1992) will rise at least 8 inches (0.2 meters) and no more than 6.6 feet (2 meters) by 2100."